Gas-Tight Pharmaceutical Bottle Closure

ABSTRACT

A gas-tight pharmaceutical container includes a pharmaceutical bottle defining a main enclosure and an upper neck forming a top opening. The upper neck includes an upper rim forming a planar engagement surface. A screw-on closure cap seals the top opening, and includes a circular top member and a circumferential flange. In one embodiment, the closure cap is metal and includes an annular pliable gasket secured to a peripheral portion thereof and a layer of lacquer applied interiorly of the gasket. In another embodiment, the closure cap is plastic and includes a circular inner liner formed by a base layer, a foil layer adjacent to the base layer, and an annular pliable gasket secured to the foil layer. With either embodiment, threaded engagement of the screw-on closure cap with the pharmaceutical bottle under pressure causes the pliable gasket to sealingly engage the upper rim to provide a gas-tight seal.

BACKGROUND OF THE INVENTION

Various products are provided in sealed containers in order to preservethe products in the container and prevent degradation. Pharmaceuticals,especially pharmaceuticals which are oxygen-sensitive or highlyoxygen-sensitive, such as ultra-oxygen-sensitive levothyroxine sodiumtablets, capsules or the like, are one type of product where a good andreliable seal at the open top of the pharmaceutical bottle is importantto prevent oxygen in the atmosphere as well as moisture from any sourcefrom coming in contact with the pharmaceuticals in the bottle andunnecessarily degrading the pharmaceuticals. For that reason,pharmaceutical containers often include an oxygen scavenger therein, inaddition (typically) to a foil seal attached by induction heat sealingto the open top of the bottle and underneath a removable cap providedfor the bottle. This foil seal is used after manufacture of the filledbottle, during shipping and prior to opening by the user, at which timethe foil seal is removed or destroyed. However, the provision of such afoil seal has proven to be difficult and complex, posing more problemsthan the closing of the containers themselves.

In the prior art, a very common foil seal for a pharmaceutical bottle atthe open top thereof is a heat-sealed foil laminate thermo-adhered tothe upper rim or finish of the top of the pharmaceutical bottle. Such afoil laminate is typically used together with a) a metal cap having apulp liner and a layer of foil adhered to the pulp liner, or b) aplastic cap with a foil laminate liner under a thermo-plastic coating ofthe cap top. However, the effectiveness of such thermo-adhered foillaminates to the open top of the bottle is dependent on the seal betweenthe bottle and the thermo-adhered foil laminate since heat-sealing(especially polyethylene) bottles, even when done properly, is adifficult operation. This heat-sealing of the thermo-adhered foillaminate to the open top is difficult or undesirable because:

-   -   the heat-sealing equipment is complex, and dependent on        temperature and dwell time;    -   the heat-sealed bottles typically need a “re-torqueing”        operation after the sealed containers and applied caps have        cooled;    -   the heat-sealing process itself exposes the contents to        thermo-degradation and possibly detrimental degradation, such as        from the glue fumes;    -   the heat-sealing is difficult or ineffective if the tops or        finishes of the bottles have irregularities (probably the main        cause of failure before opening by the user);    -   the removal of the thermo-adhered foil laminate from the tops of        the bottles is an irritation to users; and    -   after removal (or more typically partial removal) of the        thermo-adhered foil laminate, re-sealing is practically        impossible with the remaining top (having only a pulp/foil liner        or foil laminate) and the uneven surface of the open top of the        bottle.

Thus, there is a need in the art for an alternative to thethermo-adhered foil laminate for sealing and resealing of apharmaceutical bottle or the like.

BRIEF SUMMARY OF THE INVENTION

Thus, in accordance with the present invention, a gas-tightpharmaceutical container is provided including a pharmaceutical bottledefining a main enclosure and an upper neck extending from the mainenclosure and forming a top opening for the main enclosure as well ashaving external screw threads thereabout. The upper neck also includesan upper rim forming a planar engagement surface about the top opening.The pharmaceutical container also includes a metal screw-on closure capused to seal the top opening of the bottle. This closure cap includes acircular top member and a circumferential flange depending downwardlyfrom the top member and defining an interior area of the top member. Theflange has internal screw threads which mate with the external screws ofthe upper neck to secure the closure cap under pressure to the planarengagement surface of the upper neck of the main enclosure. The closurecap also includes an annular pliable gasket secured to a peripheralportion of the interior area of the top member and a layer of lacquerapplied to the interior area of the top member inside of the gasket.With this construction, threaded engagement of the screw-on closure capwith the pharmaceutical bottle under pressure causes the pliable gasketto sealingly engage the upper rim of the pharmaceutical bottle toprovide a gas-tight seal.

The material of the closure cap is preferably either aluminum or steel,while the pharmaceutical bottle is preferably a plastics material. Thematerial of the pliable gasket is preferably one of butyl, silicone,nitrile or fluoroelastomer.

Also in accordance with the present invention a second embodiment of agas-tight pharmaceutical container is provided including apharmaceutical bottle as described above. The pharmaceutical containeralso includes a screw-on closure cap much as noted above, except thatthis second embodiment includes a circular inner liner which extendsover the interior area of the top member of the closure cap. This innerliner includes a base layer which is secured to the interior area of thetop member at the top of the flange, a foil layer adjacent to the baselayer, and an annular pliable gasket secured to a peripheral area of thefoil layer. Then, as with the first-mentioned pharmaceutical container,threaded engagement of the screw-on closure cap with the pharmaceuticalbottle under pressure causes the pliable gasket to sealingly engage theupper rim of the pharmaceutical bottle to provide a gas-tight seal.

In this second embodiment, the foil layer is preferably adhered to thebase layer. In addition, the material of the pliable gasket ispreferably one of butyl, silicone, nitrile or fluoroelastomer. Alsopreferably, the material of the pharmaceutical bottle is a plasticsmaterial and the material of the closure cap is a plastics material.

It is thus a feature of the present invention that an effective seal isprovided between a cap and bottle which seals the bottle aftermanufacture and before use by the user, as well as after the first useand each subsequent use by the user.

It is also a feature of the present invention that an effective seal isprovided which is simple and reliable, as well as being effectivelyresealable after each use.

Other features and advantages of the present invention are stated in orapparent from detailed descriptions of presently preferred embodimentsof the invention found hereinbelow.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a cross sectional elevation view of a top portion of agas-tight pharmaceutical bottle of the present invention including aclosure cap.

FIG. 2 is a bottom view of the closure cap for the gas-tightpharmaceutical bottle depicted in FIG. 1.

FIG. 3 is cross-sectional elevation view of a portion of the closure capidentified by the broken line 3 in FIG. 1.

FIG. 4 is a cross sectional elevation view of a top portion of a secondembodiment of a gas-tight pharmaceutical bottle of the present inventionincluding another closure cap.

FIG. 5 is a bottom view of the closure cap for a gas-tightpharmaceutical bottle depicted in FIG. 4.

FIG. 6 is cross-sectional elevation view similar to FIG. 3 but of aportion of still another closure cap.

DETAILED DESCRIPTION OF THE INVENTION

With reference now to the drawings in which like numerals represent likeelements throughout the views, there is disclosed in FIG. 1 apharmaceutical container 10 according to a first embodiment of thepresent invention. In FIG. 1, only a top portion of a gas-tight (andhence liquid-tight) pharmaceutical bottle 12 of pharmaceutical container10 is schematically shown. Pharmaceutical bottle 12 is made of asuitable material in order to prevent any transfer of oxygen (or othergases, or moisture) in the atmosphere or environment through the wallsthereof, as the oxygen (or other gases or liquids) would potentiallydamage pharmaceuticals inside, such as oxygen-sensitive pharmaceuticalsor the like in any form (tablets, capsules, coated tablets, etc.), andespecially ultra-oxygen-sensitive levothyroxine sodium tablets, capsulesor the like. In this embodiment, pharmaceutical bottle 12 is designedfor use by pharmacists, and thus holds large quantities (e.g., 1000) oftablets, capsules, or the like. Bottle 12 is thus made of a suitableplastics material such as high density polyethylene or polypropylenewhich are well known in the art for preventing oxygen ingress or whichis well-known for preventing oxygen ingress together with a suitablelining layer; but pharmaceutical bottle 12 could also be glass or otherlike materials which prevent gas or liquid transfer therethrough ifdesired.

Pharmaceutical bottle 12 is only partially shown, but is typical of suchbottles known in the art and is thus only schematically depicted inFIG. 1. Pharmaceutical bottle 12 includes a main enclosure 14 (onlypartially shown) with an upper neck 16 extending vertically therefrom.Upper neck 16 includes external screw threads 18, and upper neck 16forms a top opening 20 for main enclosure 14 by which thepharmaceuticals in bottle 12 can be accessed (dispensed, spooned, shakenor poured out) by the user. An upper rim 22 is presented at the topmostpart of upper neck 16, with upper rim 22 forming a planar engagementsurface about top opening 20.

In order to provide a gas-tight closing of top opening 20 of mainenclosure 14, pharmaceutical bottle 12 additionally includes a metalscrew-on closure cap 26 as additionally shown in FIGS. 2 and 3. Closurecap 26 is not of the child-resistant type in view of its intended use bypharmacists (or alternatively by those not desiring a child-resistantcap with a regular sized pharmaceutical bottle). Conveniently, closurecap 26 is made of a suitable metal such as aluminum or steel as desired.Closure cap 26 includes a circular top member 28 having acircumferential flange 30 extending downwardly from a periphery thereofso as to define an interior area 32 of top member 28. Flange 30 hasinternal screw threads 34 which mate with external screw threads 18 ofupper neck 16 to secure closure cap 26 under pressure (torqueing of theclosure cap) to planar engagement surface of upper rim 22 of mainenclosure 14.

The gas-tight closing supplied by closure cap 26 is provided by anannular pliable gasket 36 which is held in place or secured to aperipheral portion of interior area 32 of top member 28. Gasket 36preferably has an outer convex shape and an inner flat shape as shown,whereby the convex shape can be suitably compressed to provide thegas-tight seal against upper rim 22 while the flat shape maintains itsshape as it is pressed against the flat inside surface of top member 28.Gasket 36 is suitably made of butyl, silicone, nitrile orfluoroelastomer (such as VITON), or other acceptable pliant materials asknown in the art, and it is sized to fit snuggly inside of flange 30 inorder to be elastically held in place or in order to be adhered in placeto the peripheral portion of interior area 32. In order to protect thepharmaceuticals from the metal of closure cap 26, and vice versa, alayer of lacquer 38 (whose size is exaggerated in FIG. 3 in order to beeasily seen) is applied to interior area 32 of top member 28 at leastinside of gasket 36. In operation then, the torqueing threadedengagement of screw-on closure cap 26 with pharmaceutical bottle 10under pressure causes pliable gasket 36 to be compressed and thus tosealingly engage upper rim 22 of pharmaceutical bottle 12 to provide agas-tight seal for top opening 20.

Depicted in FIGS. 4 and 5 is a pharmaceutical container 50 according toa second embodiment of the present invention. In FIG. 4, a top portionof a gas-tight pharmaceutical bottle 52 of pharmaceutical container 50is schematically shown. Pharmaceutical bottle 52 in this embodiment isdesigned for consumer use to hold a single prescription (e.g., 10-100+,as desired). Bottle 52 is made of a suitable plastics material such ashigh density polyethylene or polypropylene, or a suitable plasticsmaterial coated with a suitable layer such as various resins or fluoridecompounds, in order to prevent any transfer of oxygen in the atmosphere(or other gases or liquids) through the walls thereof in the same manneras pharmaceutical bottle 12. Pharmaceutical bottle 52 includes a mainenclosure 54 with an upper neck 56 extending therefrom. Upper neck 56includes external screw threads 58, and upper neck 56 forms a topopening 60 for main enclosure 54 by which the pharmaceuticals in bottle52 can be accessed by the user. An upper rim 62 is presented at thetopmost part of upper neck 56, with upper rim 62 forming a planarengagement surface about top opening 60.

In order to provide a gas-tight closing of top opening 60 of mainenclosure 54, pharmaceutical bottle 52 additionally includes a plasticscrew-on closure cap 66 as additionally shown in FIG. 5. Closure cap 66is conveniently made of a suitable plastics material as known in the artsuch as polypropylene in order to be sufficiently strong or robust.Closure cap 66 includes a circular top member 68 having acircumferential flange 70 extending downwardly from a periphery thereofso as to define an interior area 72 of top member 68. Flange 70 hasinternal screw threads 74 which mate with external screw threads 58 ofupper neck 56 to secure closure cap 66 under torqueing pressure toplanar engagement surface upper rim 62 of main enclosure 54. Sincebottle 52 is designed for consumer use, surrounding closure cap 66 tomake closure cap 66 child-resistant as well known in the art is afloating outer cap 86 (only partially shown in FIG. 5). Outer cap 86 isheld loosely to closure cap 66 by a foot 88 at the bottom thereof, aswell known in the art. Finally, pressing down on outer cap 86 allowsscrewing and unscrewing of closure cap 66 by virtue of matingengagements 90 as also well known in the art.

The gas-tight closing supplied by closure cap 66 is provided by acircular inner liner or backer 76 which extends over interior area 72 oftop member 68. This inner liner 76 includes an uppermost (wax cardboard,pulp, plastic, foam or the like) base layer 78 which is fittingly heldin place or lightly secured to interior area 72 of top member 68 at thetop of flange 70. Inner liner 76 also includes, below base layer 78 andhence facing the pharmaceutical in bottle 52, an aluminum foil layer 80,or any other suitable layer which provides an oxygen (or other gas andliquid) impermeable layer to prevent ingress of oxygen through theplastic material of top member 68 of closure cap 66. Finally, as shown,an annular pliable gasket is secured, either adhered or elastically heldin place, to a peripheral area of foil layer 80 to provide a gas-tightseal in the same manner as gasket 36 discussed above. Foil layer 80 caneither be adhered to base layer 78, or be free floating and insteadadhered to gasket 82 which is held elastically in place similar togasket 36. In operation then, threaded engagement of screw-on closurecap 66 (through pressing engagement on outer cap 86) with pharmaceuticalbottle 50 under torqueing pressure causes pliable gasket 82 (togetherwith base layer 78) to sealingly engage upper rim 62 of pharmaceuticalbottle 52 to provide a gas-tight seal for top opening 60.

Depicted in FIG. 6 is a cross section (similar to that of FIG. 3) of atop portion of an alternative closure cap 96. Closure cap 86 is muchlike closure cap 26 or closure cap 66, and includes an annular pliablegasket 36 adjacent thereto, either secured thereto by adhering or thelike or floating but held in place by a resilient fit with thecircumferential flange of closure cap 86. It will be appreciated thatclosure cap 86 is made of a suitable material, either metal or plastic,which by itself is satisfactory for preventing oxygen or other egress. Asuitable plastic material would be the same as that (and with a likecoating, if any) of the bottle, or a suitable metal (not requiring acoating) such as aluminum.

With any of the constructions described above, it will be appreciatedthat the following is achieved with both disclosed embodiments:

-   -   a simple gas-resistant annual ring gasket is employed;    -   the simple ring gasket can be used with child-resistant as well        as non child resistance containers;    -   the complications of heat sealing a foil laminate are avoided;    -   no re-torqueing of the closure cap after cooling of a seal is        needed;    -   the temperature of the pharmaceutical bottle contents is not        raised when the seal is provided;    -   the use of a pliant annular gasket helps to provide a good and        reliable seal, even where there are some minor surface        irregularities on the upper rim around the open top;    -   the opening and closing of the bottle using the closure cap is        simple;    -   re-sealing of the main closure and then re-opening at the next        use is easy and reliable, requires little effort, and can be        easily accomplished by most users;    -   the closure cap can be used on a variety of pharmaceutical        bottles, including glass as well as plastic; and    -   the gasket remains in the closure cap at all times, so a new        seal is always reliably provided after each use.

It is an advantage of the present invention that the use of the rubbergasket eliminates the need for the induction heating and sealing of theprior art glue/seal provided on the foil disk, which prior art foil discwas adhered to the lips of the mouth of the container and formed a sealtherewith. However, it will be appreciated that the peeling of the priorart foil disc also acted as a tamper-evident feature, whichtamper-evidence is not part of the present invention since the foil discremains in the closure cap to effect a good barrier together with thegasket each time the cap is re-applied. Thus, it is contemplated that adifferent tamper-evident seal would be employed with the presentinvention, such as a shrink wrap around the cap or the like as wellknown in the art.

The present invention has been described as being applicable topharmaceutical containers or the like. However, it will be appreciatedthat the invention would also be applicable to other products requiringsealing from the environment, such as nutritional products likerapidly-oxidized nuts or other foods.

While the present invention has been described with respect to exemplaryembodiments thereof, it will be understood by those of ordinary skill inthe art that variations and modifications can be effected within thescope and spirit of the invention.

I claim:
 1. A gas-tight pharmaceutical container comprising: apharmaceutical bottle including a main enclosure, an upper neckextending from said main enclosure and forming a top opening for saidmain enclosure, said upper neck including external screw threads, and anupper rim of said upper neck forming a planar engagement surface of saidupper neck about said top opening of said upper neck; a metal screw-onclosure cap which is used to seal said top opening of said bottle and torepeatedly re-seal said top opening after a removal of said closure cap,said closure cap including a circular top member, and a circumferentialflange depending downwardly from said top member and defining aninterior area of said top member, said flange having internal screwthreads which mate with said external screws of said upper neck tosecure said closure cap under pressure to said planar engagement surfaceof said upper neck of said main enclosure, and an annular pliable gasketsecured to a peripheral portion of said interior area of said topmember; whereby threaded engagement of said screw-on closure cap withsaid pharmaceutical bottle under pressure causes said pliable gasket tosealingly engage said upper rim of said pharmaceutical bottle to providea gas-tight seal.
 2. A pharmaceutical container as claimed in claim 1,wherein said closure cap is aluminum.
 3. A pharmaceutical container asclaimed in claim 1, wherein said closure cap is steel, and furtherincluding a layer of lacquer applied to said interior area of said topmember inside of said gasket.
 4. A pharmaceutical container as claimedin claim 1, wherein a material of said pliable gasket is one of butyl,silicone, nitrile or fluoroelastomer.
 5. A pharmaceutical container asclaimed in claim 1, wherein said pharmaceutical bottle is made of aplastics material.
 6. A pharmaceutical container as claimed in claim 1,further including a layer of lacquer applied to said interior area ofsaid top member inside of said gasket.
 7. A pharmaceutical container asclaimed in claim 1, wherein said gasket is adhered to said interior areaof said top member.
 8. A pharmaceutical container as claimed in claim 1,wherein said gasket is resiliently held in place by said circumferentialflange in a position immediately adjacent said interior area of said topmember.
 9. A gas-tight pharmaceutical container comprising: apharmaceutical bottle including a main enclosure, an upper neckextending from said main enclosure and forming a top opening for saidmain enclosure, said upper neck including external screw threads, and anupper rim of said upper neck forming a planar engagement surface of saidupper neck about said top opening of said upper neck; a screw-on closurecap which is used to seal said top opening of said bottle and torepeatedly re-seal said top opening after a removal of said closure cap,said closure cap including a circular top member, and a circumferentialflange depending downwardly from said top member and defining aninterior area of said top member, said flange having internal screwthreads which mate with said external screws of said upper neck tosecure said closure cap under pressure to said planar engagement surfaceof said upper neck of said main enclosure; and a circular inner linerwhich extends over said interior area of said top member of said closurecap, said inner liner including a base layer which is secured to saidinterior area of said top member at the top of said flange, a foil layeradjacent to said base layer, and an annular pliable gasket secured to aperipheral area of said foil layer; whereby threaded engagement of saidscrew-on closure cap with said pharmaceutical bottle under pressurecauses said pliable gasket to sealingly engage said upper rim of saidpharmaceutical bottle to provide a gas-tight seal.
 10. A pharmaceuticalcontainer as claimed in claim 6, wherein said foil layer is adhered tosaid base layer.
 11. A pharmaceutical container as claimed in claim 6,wherein a material of said pliable gasket is one of butyl, silicone,nitrile or fluoroelastomer.
 12. A pharmaceutical container as claimed inclaim 6, wherein said pharmaceutical bottle is made of a plasticsmaterial, and wherein said closure cape is made of a plastics material.13. A pharmaceutical container as claimed in claim 9, wherein saidgasket is resiliently held in place by said circumferential flange in aposition immediately adjacent said foil layer.
 14. A pharmaceuticalcontainer as claimed in claim 9, wherein said gasket is adhered in heldin place to said foil layer.
 15. A pharmaceutical container as claimedin claim 9, wherein said base layer is made of wax cardboard.
 16. Apharmaceutical container as claimed in claim 9, wherein said base layeris made of a pulp material.
 17. A pharmaceutical container as claimed inclaim 9, wherein said closure cap is child-resistant and furtherincludes an outer cap about said top member and flange.